Windows 10 Build 18875 is the latest Insider Preview build at the moment of this writing. Microsoft has released it to Insiders in both Fast Ring and Skip Ahead. Unfortunately, there is some issue with this build, so many users are getting Error 0x80242016. It appears as 'error 0x80242016: Windows 10 Insider Preview 18875.1000 (rs_prerelease)' from WindowsUpdateClient in the event log. Here is a fix.